/*
 * Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 1999-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.sun.org.apache.regexp.internal;

/**
 * This is a class that contains utility helper methods for this package.
 *
 * @author <a href="mailto:jonl@muppetlabs.com">Jonathan Locke</a>
 */
public class REUtil {

  /**
   * complex:
   */
  private static final String complexPrefix = "complex:";

  /**
   * Creates a regular expression, permitting simple or complex syntax
   *
   * @param expression The expression, beginning with a prefix if it's complex or having no prefix
   * if it's simple
   * @param matchFlags Matching style flags
   * @return The regular expression object
   * @throws RESyntaxException thrown in case of error
   */
  public static RE createRE(String expression, int matchFlags) throws RESyntaxException {
    if (expression.startsWith(complexPrefix)) {
      return new RE(expression.substring(complexPrefix.length()), matchFlags);
    }
    return new RE(RE.simplePatternToFullRegularExpression(expression), matchFlags);
  }

  /**
   * Creates a regular expression, permitting simple or complex syntax
   *
   * @param expression The expression, beginning with a prefix if it's complex or having no prefix
   * if it's simple
   * @return The regular expression object
   * @throws RESyntaxException thrown in case of error
   */
  public static RE createRE(String expression) throws RESyntaxException {
    return createRE(expression, RE.MATCH_NORMAL);
  }
}
